The invention is directed to an improved lamination process of a photopolymerizable film onto a substrate employing a liquid which is present during the application of film to the substrate.
Lamination of a photosensitive material onto a substrate employing an intermediate liquid layer is taught in several U.S. patents using various liquids and application techniques. U.S. Pat. No. 3,629,036 discloses application of a liquid adhering agent, preferably a solvent for a resist containing a small amount of dissolved resist, to a surface of a substrate followed by application of a photosensitive resist film. U.S. Pat. No. 4,069,076 discloses a process for applying a photoresist film to a preimaged pattern relief substrate after flooding the substrate with a solvent or a nonsolvent swelling agent. U.S. Pat. No. 4,293,635 discloses application of a photosensitive composition containing an amphoteric interpolymer to a copper surface wetted with a liquid such as an ethanol-water solution.
U.S. Pat. No. 4,506,004 discloses various embodiments of obtaining printed wiring boards by means of a two layer composite coating. In one embodiment an adhesive photopolymer layer is applied to a printed wiring board in a liquid state displacing air from the printed wiring board surface. A dry film solder mask is temporarily adhered to the underside of a screen printing frame and applied onto the liquid layer prior to processing of the photopolymer layer. In another of the embodiments of the patent nonphotoimaging epoxy layers can be employed.